Warnstorfia has been sometimes treated as a section (Brotherus 1908), a subgenus (Tuomikoski 1949) or a synonym (Crosby & Magill 1981) of Drepanocladus. Tuomikoski and Koponen (1979) and Hedenäs (1993) considered it a distinct genus separated from Drepanocladus. Crosby et al. (2000) accepted nine species of Warnstorfia in the world. Two species are recognized in China.